Observation of Simultaneous Axial and Transverse Classical Heat Transport in a Magnetized Plasma

The transport of heat deposited by a small low voltage electron beam in a strongly magnetized plasma is studied for a time interval in excess of two thousand ion gyro-periods. Electron temperatures are observed to evolve along and across the magnetic field at the classically predicted rates up to times approaching one thousand gyro-periods. At later times the onset of low frequency fluctuations (below one tenth the ion gyrofrequency) coincides with departures from classical behavior. PACS: 52.25 Fi, 52.50 Gj, 52.35 Qz The theoretical foundations of heat transport due to Coulomb collisions (i.e., classical transport) in strongly magnetized plasmas (i.e., electron gyrofrequency much larger than the Coulomb collision frequency, e ie) have been known1,2,3 for nearly half a century. However, this intrinsically anisotropic phenomenon has been extremely difficult to observe in the laboratory for both fundamental reasons and lack of suitable experimental facilities. It i